828 REPORT— 1898. 



survival of tlie other, I think his exact mathematical and dynamical knowledge 

 would have prevented him from givino^ an affirmative answer. But short of this 

 aihrmative answer, his other statements, it seems to me, fall to the ground. 



I am convinced that the tenacity with which Pasteur fought against the 

 doctrine of spontaneous generation was not unconnected with his belief that 

 chemical compounds of one-sided asymmetry could not arise save under the 

 intitience of life. 



Should any one object that the doctrine of the asymmetric carbon atom is a 

 somewhat hypothetical foundation on whicli to build such a superstructure of 

 argument as the foregoing, I would point out that the argument is in reality 

 independent of this doctrine. All that I have said regarding the molecular 

 asymmetry of naturally occurring optically active organic compounds, and all the 

 geometrical considerations based thereon, hold good equally of the hemihedral 

 tfryste/Ziwe forms of these compounds, about which there is no hypothesis at all. 

 The production of a compound crystallising in one hemihedral form to the exclu- 

 sion of the opposite hemihedral form, as in the case of the tartaric acid of the 

 grape, is a phenomenon inexplicable on the assumption that merely mechanical, 

 symmetric forces are at work. Nor is this conclusion invalidated even if we 

 ultimately have to admit that the connection between molecular and crystalline 

 asymmetry is not an invariable one — a point about which there is some dispute. 



At the close of the lectures from which I have so frequently quoted, Pasteur, 

 with full confidence in the importance of his work, but without any trace of 

 personal vanity, says : — 



' It is the theory of molecular asymmetry that we have just established — one of 

 the most exalted chapters of science. It was completely unforeseen, and opens to 

 physiology new horizons, distant but sure.' 



I must leave physiologists to judge how far they have availed themselves of 

 the new outlook which Pasteur opened up to them. But if I have in any way 

 cleared the view towards one of these horizons, I shall feel that I have not 

 occupied this chair in vain. 



Some of my hearers, however, may think that, instead of rendering the subject 

 clearer, I have brought it perilously near to the obscure region of metaphysics ; and 

 certainly, if to argue the insufficiency of the mechanical explanation of a phe- 

 nomenon is to be metaphysical, I must plead guilty to tbe charge. I will, there- 

 fore, appeal to a judgment — metaphysical, it is true, but to be found in a very 

 «xact treatise on physical science — namely, rs'ewton's 'Principia.' It has a marked 

 bearing on the subject in hand : — 



' A ccBca necessitate metaphysica, qua vtique eadem est semper et ubique, nulla 

 oritur rerum variatio.' 



I will merely add that this is certainly true of the particular renon ran'atio 

 in which optically active organic compounds originate. 



The following Papers and Keports were read : — 



1. On the Extraction from Air of the Com2yanions of Argon and on Neon. 

 By William Ramsay and Morris W. Travers. 



In the Presidential Address to the Chemical Section of this Association, delivered 

 last year at Toronto, it was pointed out that the densities of helium and argon 

 being respectively 2 and 20 in round numbers, and the ratio of their specific heats 

 being in each case 1'6G, their atomic weights must be respectively 4 and 40. If 

 the very probable assumption is made that they belong to the same group of 

 elements, it appears almost certain on the basis of the Periodic Table that another 

 element should exist, having an atomic weight higher than that of helium by .about 

 16 units, and lower than that of argon by about 20. There is also room for 



